A psychologist who examined 14 inmates who are now on Texas’ death row — and two others who were subsequently executed — and found them intellectually competent enough to face the death penalty agreed on Thursday never to perform such evaluations again. Attorneys for the 14 inmates hope the agreement will help their clients, who they argue are mentally handicapped, to escape lethal injection.

As part of a settlement, the Texas State Board of Examiners of Psychologists issued a reprimand against Dr. George Denkowski, whose testing methods have been sharply criticized by other psychologists and defense attorneys as unscientific. Denkowksi agreed not to conduct intellectual disability evaluations in future criminal cases and to pay a fine of $5,500. In return, the board dismissed the complaints against him.

Texas defense lawyers and forensic psychologists across the nation have watched the case closely. Although Denkowski admitted no wrongdoing and defends his practice, those critical of his methods said the settlement could give those inmates still on death row an important appellate opportunity. “It really suggests that he screwed up,” said Dick Burr, an attorney who represents Steven Butler, a death row inmate, and who was one of the attorneys who filed a complaint against Denkowksi.

The U.S. Supreme Court ruled in 2002 that states cannot execute mentally handicapped people. But the court didn’t provide guidelines for determining whether a person is mentally handicapped, leaving it up to the states to create criteria. Texas courts have generally adopted a three-part definition that requires the convicted inmate to have below average intellectual function, lack adaptive behavior skills and to have had these problems since a young age.

Denkowski was an expert witness who prosecutors — particularly in Harris County — relied upon to perform psychological tests to determine whether a murder suspect would be eligible for execution. In 2009, other psychologists and defense lawyers complained to the board of psychologist examiners that Denkowski used unscientific methods that artificially inflated intelligence scores to make defendants eligible for the death penalty.

Denkowski published a 2008 article in the American Journal of Forensic Psychology describing his technique for scoring defendants. He said that traditional tests did not compensate for social and cultural factors. For example, he wrote, those who come from impoverished backgrounds may not have learned basic skills like using a thermometer or maintaining hygiene simply because those skills were not valued in their community. But that did not necessarily indicate a lack of intellectual function, he said.

Denkowski also explained why he deviated from the standard use of a test that evaluates adaptive behavior, or life skills. The test is typically administered to family and friends who know the person to ask about how the person functions, whether he is able to pay rent, fill out job applications, read menus and the like. But Denkowksi administered that test to the inmate instead. People close to the individual, he wrote, “tend to understate a defendant’s actual functioning markedly” because they don’t want their friend or family member to face execution.

Other psychologists have rejected Denkowski’s methods, arguing that they have no scientific basis. The American Association on Intellectual and Developmental Disabilities in its 2010 manual for classifying intellectual disability strongly cautioned against using Denkowski’s methods “until firmly supported by empirical evidence.”

“What Denkowski has been doing is a pretty radical departure,” said Marc J. Tassé, director of the Ohio State University Nisonger Center and an expert in developmental disabilities. “There’s absolutely no scientific basis to his procedure.”

There’s no evidence, Tasse said, that a person from a poor family is less likely to learn basic life skills. He said he knew of no other forensic psychologist who uses similar methods. “Basically, what he’s saying is that our standardized tests are invalid,” Tasse said.

Jennifer Andrews, Denkowski’s attorney, said her client vigorously denies that he violated any psychology board rules. Part of the problem, she said, is that the board has not promulgated specific rules for conducting forensic evaluations involving mentally handicapped individuals. There is no consensus, she said, for how those tests should be conducted. “Psychologists are left to use their best clinical judgment, which Dr. Denkowski used,” she said.

In 2007, state District Judge Mark Ellis concluded in the case of death row inmate Daniel Plata that Denkowski’s methods did not align with accepted psychological practices and ethical guidelines. Ellis threw out the 2005 evaluation Denkowksi conducted, writing that it “must be disregarded due to fatal errors in … administration and scoring.” Plata’s sentence was commuted to life in 2008, and he is now at the Hodge Unit with other developmentally disabled prisoners.

In his 2006 evaluation of Steven Butler, who was convicted in the shooting death of a store clerk, Denkowski rejected other IQ test scores that indicated Butler was well below average intelligence. He discounted behavioral evaluations from Butler’s family and friends, who said the young man couldn’t understand the rules of basketball, had to have others read menus for him and that he had failed basic classes.

The U.S. 5th Circuit Court of Appeals has stayed Butler’s execution pending the outcome of the complaint against Denkowksi. A clause in the settlement asserts that the agreement can’t be cited in capital punishment appeals, but Burr said he plans to use it — and Denkowski’s agreement not to conduct forensic evaluations again — to argue that Butler should be re-evaluated to ensure that Texas doesn’t execute a mentally handicapped man. “I will certainly be arguing to the courts that his agreement not to do anymore forensic evaluations means something,” Burr said.

State Sen. Rodney Ellis, D-Houston, chairman of the Innocence Project board and a member of the Criminal Justice Committee, said every case involving Denkowski should be reviewed by the courts. “We cannot simply shrug our shoulders and sit by and watch while the state uses legal technicalities to execute these intellectually disabled men,” he said, “especially on the word of someone who is no longer permitted to make these kinds of determinations.”

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